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111.
The melting process of constrained nylon 6 fibers has been studied to estimate the true melting point of its original crystals.
The melting peak became simpler in shape and shifted to higher temperature with increasing fiber-axis restricting force. When
heating rate, β, was increased, the temperature where the melting curve initially departs from its baseline, Tsm, decreased
steeply in the range of 45 to 60°C min-1, and increased linearly with increasing β above 60°C min-1. By linear extrapolation of Tsm to 0°C min-1, the temperature of ca 190°C was obtained for the melting temperature of the original nylon 6 crystals. This seems to correspond
to the zero-entropy-production melting of the most imperfect crystallites of the nylon 6 fabric.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
112.
113.
V. R. Kartashov T. N. Sokolova A. Yu. Pavinskii I. V. Timofeev A. B. Radbil' 《Russian Chemical Bulletin》1995,44(12):2375-2381
The kinetics of azidomercuration of alkenes, cycioalkenes, and their derivatives with a Hg(OAc)2-NaN3 system (1 1, 1 2, and 1 3) was studied. Based on the data on the product structure and kinetic results, it was concluded that HgOAcN3 and Hg(N3)2 play the role of azidomercuration reagents. The reactions with alkenes having a strained double bond occur by a concerted scheme. With nonstrained alkenes, a multistep mechanism is realized, its first reversible step involving the formation of a mercurinium intermediate with an ion pair structure.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No.12, pp. 2479–2485, December, 1995. 相似文献
114.
115.
In relation to a colloid stability, the adsorption structure of the Stern layer on a sessile mercury electrode in a thin liquid film of nonionic surfactant was investigated by measuring the double layer capacitance. The Stern capacitance on the electrode in the film could be detected when the measuring frequency used was low, for the resistance of the film was not extremely high but of the order of several thousand ohm. It was found that the adsorption structure of nonionic surfactant in the thin liquid film shows a stratification different from that of bulk. 相似文献
116.
117.
Z. Mikulová P. Čuba J. Balabánová T. Rojka F. Kovanda K. Jirátová 《Chemical Papers》2007,61(2):103-109
The effect of hydrothermal treatment on properties (crystallinity, porous structure, reducibility, acidity, basicity, and
catalytic activity and selectivity in toluene and ethanol total oxidation) of Ni—Al layered double hydroxide precursors and
related mixed oxides was examined. The hydrothermal treatment increased considerably both the content of crystalline phase
and LDH crystallite size. On the other hand, only a slight effect of the precursor hydrothermal treatment on crystallinity
of the related Ni—Al mixed oxides obtained by calcination at 450°C was observed. The reducibility of NiO particles appeared
to be hindered considerably compared to the reducibility of pure NiO. Catalytic activity of the Ni—Al mixed oxides prepared
from the precursors hydrothermally treated for a short time (4 h) was the highest. The highest amount of acetaldehyde formed
during the total oxidation of ethanol, i.e. the worst selectivity was found for the calcined Ni—Al LDH without hydrothermal treatment.
Presented at the 33rd International Conference of the Slovak Society of Chemical Engineering, Tatranské Matliare, 22–26 May
2006. 相似文献
118.
The relationship between the current and the bulk concentration of complex ions during concurrent specific adsorption of an electrochemically active complex ion and a complexing ligand is considered. The effect of parameters that characterize adsorption of such ions and the structure of the electrical double layer on this relationship is analyzed.__________Translated from Elektrokhimiya, Vol. 41, No. 7, 2005, pp. 817–822.Original Russian Text Copyright © 2005 by Rogozhnikov. 相似文献
119.
The inner-shell structure of some heavy atoms is examined using a self-consistent relativistic local density method. Ar(K), Kr(K) and Xe (K,L
1,L
2 andL
3) binding energies and {ie863-1} (hyper-satellite) energies of Tl, Hg and Tm are calculated. The results are compared with
available experimental data.
A part of this work was presented byMPD at the Trieste International Symposium on “Core level excitations in atoms, molecules and solids,” 22–26 June 1981, Extended
Abstracts (ed.) E Tosatti, ICTP Report No. 89/81 p. 11. 相似文献
120.
氧化物、盐类在氧化物载体表面的自发分散是一种广泛存在的现象,文献中已报导过大量氧化物和盐类在高比表面载体上分散的研究结果['-3]TIO。作为一种较新型的载体,与Y-AI。O。、硅胶等传统载体相比,有许多不同特性.活性组分在TIO。表面的分散状态及所得催化剂的性能已有不少报导['-'],但所用的TIOZ主要是较高比表面的锐钛矿型TIOZ(刘金红石型TIO。(r)和锐钛矿型TIOZ(a)的结构不同,它是高温生成相,比表面较小['].氧化物在金红石上的分散行为仍未见报导.我们制备了三种具有不同比表面的TIO水),系统地研… 相似文献